English

Electroweak Precision Observables, New Physics and the Nature of a 126 GeV Higgs Boson

High Energy Physics - Phenomenology 2015-06-16 v2

Abstract

We perform the fit of electroweak precision observables within the Standard Model with a 126 GeV Higgs boson, compare the results with the theoretical predictions and discuss the impact of recent experimental and theoretical improvements. We introduce New Physics contributions in a model-independent way and fit for the S, T and U parameters, for the ϵ1,2,3,b\epsilon_{1,2,3,b} ones, for modified ZbbˉZb\bar{b} couplings and for a modified Higgs coupling to vector bosons. We point out that composite Higgs models are very strongly constrained. Finally, we compute the bounds on dimension-six operators relevant for the electroweak fit.

Keywords

Cite

@article{arxiv.1306.4644,
  title  = {Electroweak Precision Observables, New Physics and the Nature of a 126 GeV Higgs Boson},
  author = {Marco Ciuchini and Enrico Franco and Satoshi Mishima and Luca Silvestrini},
  journal= {arXiv preprint arXiv:1306.4644},
  year   = {2015}
}

Comments

44 pages, 12 figures. v2: references added, version to appear in JHEP